Fire emergency lamp system

Abstract

The embodiment of the utility model provides a fire-fighting emergency lamp system, which comprises a variable power supply, a voltage stabilizing circuit and a control circuit, and is characterized in that the variable power supply is used for providing line voltages with different voltage values during normal power supply and abnormal power supply; the voltage stabilizing circuit is used for stabilizing the line voltage provided by the variable power supply, reducing the voltage when the line voltage rises, and providing the reduced voltage for the control circuit; the control circuit comprises an operational amplifier U1C, a first triode, a relay and an emergency lamp, the line voltage is compared with a preset voltage value through the operational amplifier, and when the line voltage is higher than the preset voltage value, a high-level signal is output to enable the first triode to be conducted, so that the relay is closed to control the emergency lamp to emit light; the emergency lamp is powered by a variable power supply. In this way, the emergency lamp is not limited by the voltage of the control circuit, a high-power lamp can be replaced according to needs, and meanwhile the circuit is simple in structure and high in stability.

Description

Technical Field

[0001] The present invention relates to the technical field of telecommunication fire protection, and in particular to a fire emergency lighting system. Background Art

[0002] In emergencies such as fires and power outages, normal lighting systems often fail due to power outages. Firefighting lights become crucial tools for guiding people to evacuate safely. Consequently, fire emergency lights and fire indicator lights (including directional and exit lights) are increasingly being installed in buildings. Conventional firefighting lighting fixtures utilize a decentralized control approach. Batteries are installed in the fixtures. When powered by an external power source, the battery is charged, placing it in a floating state. During this time, the fire indicator lights operate normally, while the power is supplied by the line. The fire emergency lights are off. In the event of a power outage, the fire indicator lights and emergency lights are powered by batteries. While the fire indicator lights remain illuminated, the fire emergency lights also need to be illuminated to facilitate evacuation or other measures. However, the scattered distribution of the fixtures throughout a building makes regular inspection and testing of the lights and batteries difficult. Even if the batteries remain undischarged for extended periods, their discharge time may not meet operational requirements due to their age. While this approach offers flexibility, it is gradually being phased out due to the aforementioned drawbacks.

[0003] The new firefighting lighting fixtures currently in use utilize centralized control. Fire emergency lights and fire indicator lights no longer have internal batteries. Instead, power is provided by a centralized control box. The centralized control box houses a battery, similar to an emergency power supply (EPS). Under normal circumstances, the control box provides 24V-36V power to the lights, with the battery in a float charge state. Under abnormal circumstances, the battery provides power to the lights. The centralized control box and firefighting lighting are powered by a single line, using NH fire-resistant wire to prevent accidental damage. Since the fire indicator lights and fire emergency lights are on the same line, under normal circumstances, the fire indicator lights are in operation and the emergency lights are off. Under abnormal circumstances, such as power outages, fires, or commissioning, the emergency lights need to be activated, requiring control from the centralized control box.

[0004] Currently, there are two common control methods: one is to use the fire protection bus (24V) to control the lamps, and the other is to add dedicated communication cables for control. However, using the fire protection bus (24V) for control has some disadvantages. First, since the rated operating voltage of the fire protection bus (24V) is typically 24V, to ensure that the lamps match the voltage provided by the bus, lamps with a 24V operating voltage are connected to the bus. However, 24V lamps have relatively low power and brightness, which reduces the practicality of fire protection lamps in abnormal lighting conditions. However, if higher-power lamps with a 36V operating voltage are replaced with higher-power lamps, when powered by the 24V operating voltage of the 24V bus, the voltage provided by the bus will not match the lamps' operating voltage due to the higher power of the lamps. To ensure proper lighting, the current flowing through the wiring will increase. Since hundreds of lamps need to be connected to the fire protection bus simultaneously, the increased current load will cause the wiring to heat up, posing a potential safety hazard. Secondly, since the power supply line and signal line of the fire protection bus No. 2 are combined into one, the technology of sharing one bus for signal and power supply is realized. However, this also means that the operating voltage of the bus No. 2 can only be maintained at 24V. If the voltage is increased, for example, to 36V, although this can achieve the connection of higher-power lamps with a 36V operating voltage with a smaller current, the increased voltage will cause signal interference, which also limits the fire protection bus No. 2 from connecting to fire protection lamps with higher operating voltages. In addition, due to the existence of signal interference, the transmitted signal has a certain instability.

[0005] Another way to control the lamps is to add dedicated communication cables. The power line and signal line are separated, so that they can be powered separately, so that lamps with higher operating voltages can be connected. However, this requires additional cable materials and laying costs, and the use of a bus controller, which increases the cost of construction and maintenance. In addition, this control method also requires the transmission of communication signals, which reduces the reliability of the control.

[0006] In summary, a centralized control method is needed that can match the voltage provided by the line with the voltage of the lamp, and can replace high-power lamps with higher operating voltages as needed. At the same time, it does not require communication signal transmission and can achieve the characteristics of simple control circuits and high stability. Utility Model Content

[0007] The purpose of the embodiment of the present invention is to provide a fire emergency lighting system, which is used to solve the problem in the prior art that when using a fire second bus power supply, only fire lamps that match the line voltage can be used, and high-power lamps with high operating voltage cannot be replaced.

[0008] To achieve the above objectives, an embodiment of the present invention provides a fire emergency lighting system, comprising: a variable power supply, a voltage stabilizing circuit, and a control circuit, wherein the variable power supply provides a line voltage of a first voltage value during normal power supply and a second voltage value during abnormal power supply, wherein the first voltage value is lower than the second voltage value; the voltage stabilizing circuit is connected to the variable power supply, and is configured to stabilize the line voltage provided by the variable power supply and, when the line voltage provided by the variable power supply is the second voltage value, reduce the second voltage value to a first voltage value and provide a voltage of the first voltage value to the control circuit; the control circuit comprises: an operational amplifier U1C, a first transistor, a relay, and an emergency light, wherein the operational amplifier U1C is configured to compare the line voltage with the first voltage value. When the line voltage provided by the variable power supply is greater than the first voltage value, the voltage connected to the non-inverting input terminal of the operational amplifier U1C is higher than the voltage connected to the inverting input terminal, and a high-level signal is output from the output terminal to the first transistor, causing the first transistor to conduct, thereby closing the relay and controlling the emergency light to emit light; the emergency light is powered by the variable power supply.

[0009] Optionally, the relay includes a normally open contact. When the relay is energized, the normally open contact is closed to short-circuit the emitter and collector of the first transistor, thereby forming a self-locking state.

[0010] Optionally, the emergency lighting system further includes an operational amplifier U1A, connected between the operational amplifier U1C and the first transistor, and the inverting input terminal of the operational amplifier U1A is connected to the output terminal to ensure that the input signal is consistent with the output signal.

[0011] Optionally, the emergency lighting system further includes a resistor R1, a resistor R2 and an adjustable resistor, wherein one end of the resistor R1 is connected to the line voltage, and the other end is connected in series with the adjustable resistor and then connected to the non-inverting input of the operational amplifier U1C; one end of the resistor R2 is connected to the output of the voltage stabilizing circuit, and the other end is connected to the inverting input of the operational amplifier U1C.

[0012] Optionally, the emergency lighting system further includes a voltage regulator tube, one end of which is grounded, and the other end of which is connected to the inverting input terminal of the operational amplifier U1C.

[0013] Optionally, the emergency lighting system further includes a first alarm and a first diode, and the first alarm and the first diode are respectively connected in parallel to both ends of the relay.

[0014] Optionally, the emergency lighting system further includes: an oscillating circuit connected to the output end of the operational amplifier U1A; a second transistor, the base of which is connected to the output end of the oscillating circuit; and a second alarm connected to the collector of the second transistor.

[0015] Optionally, the second alarm is a light emitting diode.

[0016] Optionally, the emergency lighting system further includes an operational amplifier U1D, wherein the non-inverting input terminal of the operational amplifier U1D is connected to the output terminal of the oscillation circuit, and the inverting input terminal of the operational amplifier U1D is connected to the output terminal, so as to ensure that the input signal is consistent with the output signal.

[0017] Optionally, the voltage stabilizing circuit is a three-terminal integrated voltage stabilizing circuit 7824, whose input terminal and output terminal are grounded via capacitors respectively.

[0018] Through the above technical solution, the present disclosure utilizes a voltage stabilizing circuit connected to a variable power supply. During normal power supply, the control circuit receives a lower first voltage value, and the emergency light does not operate. During abnormal power supply, the variable power supply provides a higher second voltage value, and the voltage stabilizing circuit reduces the second voltage value to the first voltage value to power the control circuit. When the control circuit detects that the line voltage is greater than the first voltage value, it outputs a high-level signal to the first transistor, thereby turning on the first transistor, thereby closing the relay and illuminating the emergency light controlled by the relay. During abnormal power supply, although the voltage increases, the voltage stabilizing circuit reduces the voltage, allowing the control circuit to operate normally at the lower first voltage value. The emergency light is powered by the variable power supply and receives the higher voltage value provided by the variable power supply during abnormal power supply. This separates the power supply circuits for the control circuit and the emergency light, thereby enabling the use of high-power lamps with any operating voltage, without being limited to lamps that match the voltage of the control circuit.

[0019] Other features and advantages of the embodiments of the present disclosure will be described in detail in the subsequent detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The accompanying drawings are used to provide a further understanding of the embodiments of the present disclosure and constitute a part of the specification. Together with the following detailed description, they are used to explain the embodiments of the present disclosure but do not constitute a limitation of the embodiments of the present disclosure. In the accompanying drawings:

[0021] Figure 1 is a structural diagram of a fire emergency lighting system provided by an embodiment of the present disclosure;

[0022] Figure 2 is a structural diagram of a fire emergency lighting system provided by another embodiment of the present disclosure;

[0023] Figure 3 is a structural diagram of a fire emergency lighting system provided by another embodiment of the present disclosure;

[0024] Figure 4 2 is a structural diagram of a voltage stabilizing circuit provided in an embodiment of the present disclosure. DETAILED DESCRIPTION

[0025] The following describes the specific implementation of the embodiment of the present disclosure in detail with reference to the accompanying drawings. It should be understood that the specific implementation described herein is only used to illustrate and explain the embodiment of the present disclosure, and is not used to limit the embodiment of the present disclosure.

[0026] Figure 1 This is a structural diagram of a fire emergency lighting system provided by an embodiment of the present disclosure. Figure 1 As shown, a fire emergency light system provided by an embodiment of the present disclosure includes: a variable power supply, a voltage stabilizing circuit, and a control circuit, wherein the line voltage provided by the variable power supply during normal power supply is a first voltage value and the line voltage provided during abnormal power supply is a second voltage value, wherein the first voltage value is lower than the second voltage value; the voltage stabilizing circuit is connected to the variable power supply, and is used to stabilize the line voltage provided by the variable power supply and, when the line voltage provided by the variable power supply is the second voltage value, reduce the second voltage value to the first voltage value and provide the first voltage value to the control circuit; the control circuit includes: an operational amplifier U1C, a first transistor, a relay, and an emergency light, wherein the operational amplifier U1C is used to compare the line voltage with the first voltage value. When the line voltage provided by the variable power supply is greater than the first voltage value, the voltage connected to the non-inverting input terminal of the operational amplifier U1C is higher than the voltage connected to the inverting input terminal, and a high-level signal is output from the output terminal to the first transistor, turning on the first transistor, thereby closing the relay and controlling the emergency light to emit light; the emergency light is powered by the variable power supply.

[0027] Specifically, in the disclosed embodiment, the variable power supply is a centralized control box, which is equipped with a battery. When the power supply is normal, the centralized control box is powered by the mains electricity, and the output is a first voltage value, usually 24V. When an emergency such as a power outage or fire occurs, the mains electricity supply is interrupted, and the centralized control box is switched to the battery for powering, and the output is a second voltage value, usually 36V. It can be understood that a voltage stabilizing circuit is connected to the variable power supply to stabilize the voltage provided by the variable power supply, and when the variable power supply provides the second voltage value, the voltage is reduced to the first voltage value to provide working power for the control circuit. Since the working voltage of the control circuit cannot exceed the second voltage value, the voltage stabilizing circuit is used so that when the received voltage value is increased to the second voltage value, the control circuit can still receive the first voltage value provided by the voltage stabilizing circuit for normal operation, thereby protecting the control circuit from damage. The control circuit uses an operational amplifier as a comparator to compare the detected line voltage with a first voltage value. When the line voltage exceeds the first voltage value, a high-level signal is output, which is then sent to the first transistor. This turns on the first transistor, and the relay connected to the first transistor also conducts, thereby energizing the relay coil and activating it, controlling the emergency light. Because the relay has a normally open contact, it remains open under normal power supply conditions, and the emergency light does not operate. Furthermore, the emergency light is powered by a variable power supply separate from the control circuit circuit. Therefore, it is not affected by the voltage of the control circuit and can be connected to a lamp with any operating voltage.

[0028] In some embodiments, the relay includes a normally open contact. When the relay is energized, the normally open contact is closed to short-circuit the emitter and collector of the first transistor, thereby forming a self-locking state.

[0029] Specifically, when a relay is used in conjunction with a transistor in a circuit, the transistor's switching action can achieve self-locking. Specifically, when a certain condition (such as an input signal) is met, the transistor conducts, energizing the relay coil and closing it. At this point, one of the relay's normally open contacts closes, short-circuiting the transistor's emitter and collector, creating a feedback loop. This feedback loop ensures that even if the input signal disappears, the transistor remains on, and the relay continues to close, creating a self-locking state. This self-locking mechanism is particularly important in short-circuit protection circuits. When a short circuit occurs, the current suddenly increases, triggering the protection mechanism. The transistor's switching action quickly disconnects the circuit, preventing damage caused by the short circuit. Furthermore, due to the self-locking mechanism, even after the short circuit is resolved, power will not be restored immediately. Instead, power will need to be manually reset or other conditions must be met before power can be restored.

[0030] Figure 2 FIG. 1 is a structural diagram of a fire emergency lighting system provided by another embodiment of the present disclosure. Figure 2As shown, the emergency light system further comprises an operational amplifier U1A connected between the operational amplifier U1C and the first transistor, with the inverting input and output of the operational amplifier U1A being connected, for ensuring consistency between the input signal and the output signal.

[0031] Specifically, the inverting input and output of the operational amplifier U1A are connected to form a voltage follower, which receives the high-level signal output by the operational amplifier U1C and transmits it to the first transistor. Since the output impedance of the voltage follower is very small, it can ensure consistency between the input signal and the output signal. It can be understood that in this embodiment, a resistor R3 is added after the operational amplifier U1A, connected between the output of the operational amplifier U1A and the base of the first transistor. Since the output impedance of the operational amplifier is usually low, some loads may require a higher input impedance to work stably. By connecting a resistor in series at the base of the transistor, the input impedance of the circuit can be adjusted to match the input impedance of the load, thereby improving the transmission efficiency and quality of the signal, and the resistor can limit the base current flowing into the transistor to prevent excessive current from damaging the transistor. In addition, the resistor can also play a role in current limiting protection when abnormal conditions occur in the circuit, preventing damage to circuit components.

[0032] The emergency light system further comprises resistors R1, R2 and an adjustable resistor, wherein one end of the resistor R1 is connected to the line voltage, and the other end is connected to the adjustable resistor in series and then connected to the non-inverting input of the operational amplifier U1C. One end of the resistor R2 is connected to the output of the voltage stabilizing circuit, and the other end is connected to the inverting input of the operational amplifier U1C.

[0033] Specifically, the resistor R1 is connected to the adjustable resistor to divide the voltage input to the non-inverting input of the operational amplifier U1C, avoiding damage to the operational amplifier when the voltage is too high. The resistor R2 is connected to the power supply for current limiting and voltage stabilization, serving as a constant voltage.

[0034] The emergency light system further comprises a voltage stabilizing tube, one end of which is grounded and the other end is connected to the inverting input of the operational amplifier U1C.

[0035] Specifically, in the operational amplifier circuit, a stable power supply voltage is needed to ensure the stability and accuracy of the circuit. However, ordinary power supply voltage may be affected by factors such as line impedance and fluctuate, thereby affecting the performance of the circuit. By connecting a voltage stabilizing tube to the inverting input of the operational amplifier, the voltage stabilizing characteristics of the voltage stabilizing tube can be used to stabilize the power supply voltage, thereby ensuring the operational stability and accuracy of the operational amplifier, and protecting the operational amplifier from damage caused by power fluctuations or abnormal voltages.

[0036] The emergency lamp system further comprises a first alarm and a first diode, which are connected in parallel across the relay.

[0037] Specifically, the first alarm is a buzzer in this embodiment, and the emergency lamp is controlled to be lighted when the coil of the relay is powered and attracted, which indicates that the power supply is abnormal and the first alarm needs to work to give an alarm. The first diode in this embodiment is a freewheeling diode, which is connected in parallel across the relay to release the current in the inductance of the relay coil through the diode when the relay is turned off, thereby protecting the first triode. The buzzer and the freewheeling diode used in this embodiment are only exemplary and not limiting.

[0038] Figure 3 is a structural diagram of a fire emergency lamp system provided by another embodiment of the present disclosure, as shown in Figure 3 The emergency lamp system further comprises an oscillation circuit connected to the output end of the operational amplifier U1A, a second triode with the base connected to the output end of the oscillation circuit, and a second alarm connected to the collector of the second triode.

[0039] Specifically, the oscillation circuit is connected to the output end of the operational amplifier U1A, and the structure and working principle of the oscillation circuit are well known to those skilled in the art. In this embodiment, the oscillation circuit is composed of an operational amplifier U1B, a clamping diode, a capacitor C1, and resistors R5, R6, R7, and R8. The oscillation circuit receives the voltage change signal output by the operational amplifier U1A and transmits the signal to the second triode. When the second triode is turned on, the second alarm works.

[0040] The second alarm is a light-emitting diode. Specifically, the second alarm is set as a light-emitting diode in this embodiment, and a resistor R19 is connected in series at the anode end of the second alarm. When the oscillation current generated by the oscillation circuit passes through the light-emitting diode, the light-emitting diode will flicker at a corresponding frequency due to the periodic change of the current, thereby playing an alarm prompt role. The resistor R19 is connected in series to limit the current, thereby protecting the second alarm and ensuring its stable operation.

[0041] The emergency lamp system further comprises an operational amplifier U1D, the non-inverting input end of which is connected to the output end of the oscillation circuit, and the inverting input end and the output end of which are connected, for ensuring that the input signal and the output signal are consistent.

[0042] Specifically, in this embodiment, a resistor R9 is added after the operational amplifier U1D, and the resistor R9 is connected between the output terminal of the operational amplifier U1D and the base of the second transistor. The operational amplifier U1D has the same function as the operational amplifier U1A, and is used to form a voltage follower to ensure that the signal output from the oscillation circuit to the second transistor is normal. The function of connecting the resistor R9 is also consistent with the function of connecting the resistor R3 to the operational amplifier U1A. In addition, since the impedance of the oscillation circuit is very small, by connecting the operational amplifier U1D, the output resistance of the oscillation circuit can be matched with the input resistance of the load, thereby achieving effective signal transmission. At the same time, there is sometimes a problem of mutual interference between the various parts of the circuit. This interference may lead to a decrease in circuit performance. By adding a voltage follower to the circuit, these mutual interferences can be effectively isolated, so that the various parts of the circuit can work more independently, improving the stability of the entire circuit.

[0043] Figure 4 is a structural diagram of a voltage stabilizing circuit provided in an embodiment of the present disclosure, such as Figure 4 As shown, the voltage stabilizing circuit is a three-terminal integrated voltage stabilizing circuit 7824, whose input terminal and output terminal are grounded via capacitors respectively.

[0044] Specifically, this embodiment uses a three-terminal integrated voltage regulator circuit 7824 as a voltage regulator circuit. The input terminal is connected to the voltage provided by the variable power supply, and the output terminal is connected to the control circuit to provide voltage to the control circuit. At the same time, capacitors connected to the input and output terminals are used to stabilize the voltage. The 7824 voltage regulator circuit is used to stabilize the voltage provided by the variable power supply to 24V and provide it to the control circuit. Because the control circuit in this embodiment is composed of an LM324 operational amplifier and a relay, its operating voltage cannot exceed 36V, otherwise there will be a risk of damage. When the variable power supply provides a second voltage value of 36V under abnormal conditions, since the voltage is already higher than 24V at this time, the 7824 voltage regulator circuit reduces the higher second voltage value to 24V to ensure the normal operation of the control circuit. When the variable power supply provides a normal power supply of 24V or less, the 7824 voltage regulator circuit outputs the corresponding actual voltage value without the need for voltage reduction.

[0045] Thus far, various embodiments of the present disclosure have been described in detail. To avoid obscuring the concept of the present disclosure, some details known in the art have not been described. Based on the above description, those skilled in the art can fully understand how to implement the technical solutions disclosed herein.

[0046] Although some specific embodiments of the present disclosure have been described in detail through examples, those skilled in the art will understand that the above examples are for illustrative purposes only and are not intended to limit the scope of the present disclosure. Those skilled in the art will understand that the above embodiments may be modified or some technical features may be replaced with equivalents without departing from the scope and spirit of the present disclosure. In particular, as long as there are no structural conflicts, the various technical features mentioned in the various embodiments may be combined in any manner.

[0047] It should also be noted that the terms "comprises," "includes," or any other variations thereof are intended to encompass non-exclusive inclusion, such that a product or device comprising a series of elements includes not only those elements but also other elements not explicitly listed, or elements inherent to such product or device. In the absence of further limitations, an element defined by the phrase "comprising a..." does not exclude the presence of other identical elements in the product or device comprising the element.

[0048] The acquisition, transmission, storage, use, and processing of data in the technical solution of this application comply with the relevant provisions of national laws and regulations.

[0049] The above are merely embodiments of the present application and are not intended to limit the present application. For those skilled in the art, the present application may have various changes and variations. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present application should all be included within the scope of the claims of the present application.

Claims

1. A fire emergency lighting system, characterized in that: The emergency lighting system comprises: Variable power supply, voltage stabilizing circuit, control circuit, The variable power supply provides a first voltage value for the line voltage during normal power supply and a second voltage value for the line voltage during abnormal power supply, wherein the first voltage value is lower than the second voltage value; The voltage stabilizing circuit is connected to the variable power supply, and is used to stabilize the line voltage provided by the variable power supply and, when the line voltage provided by the variable power supply is a second voltage value, reduce the second voltage value to a first voltage value and provide the control circuit with a voltage of the first voltage value; The control circuit includes: an operational amplifier U1C, a first transistor, a relay and an emergency light. The operational amplifier U1C is used to compare the line voltage with the first voltage value. When the line voltage provided by the variable power supply is greater than the first voltage value, the voltage connected to the non-inverting input terminal of the operational amplifier U1C is higher than the voltage connected to the inverting input terminal, and a high-level signal is output from the output terminal to the first transistor. The first transistor is turned on, thereby closing the relay and controlling the emergency light to emit light. The emergency light is powered by the variable power supply.

2. The emergency lighting system according to claim 1, characterized in that: The relay includes a normally open contact. When the relay is energized, the normally open contact is closed to short-circuit the emitter and collector of the first transistor, thereby forming a self-locking state.

3. The emergency lighting system according to claim 1, characterized in that: The emergency light system further includes an operational amplifier U1A connected between the operational amplifier U1C and the first transistor. The inverting input terminal of the operational amplifier U1A is connected to the output terminal to ensure that the input signal is consistent with the output signal.

4. The emergency lighting system according to claim 1, characterized in that: The emergency light system also includes a resistor R1, a resistor R2 and an adjustable resistor. Among them, one end of the resistor R1 is connected to the line voltage, and the other end is connected in series with the adjustable resistor and then connected to the non-inverting input terminal of the operational amplifier U1C; one end of the resistor R2 is connected to the output of the voltage stabilizing circuit, and the other end is connected to the inverting input terminal of the operational amplifier U1C.

5. The emergency lighting system according to claim 4, characterized in that: The emergency lighting system further includes a voltage regulator tube, one end of which is grounded, and the other end of which is connected to the inverting input terminal of the operational amplifier U1C.

6. The emergency lighting system according to claim 1, characterized in that: The emergency lighting system further includes a first alarm and a first diode, and the first alarm and the first diode are respectively connected in parallel to both ends of the relay.

7. The emergency lighting system according to claim 1, characterized in that: The emergency lighting system further comprises: an oscillator circuit connected to the output terminal of the operational amplifier U1A; a second triode, the base of which is connected to the output end of the oscillation circuit; and The second alarm is connected to the collector of the second transistor.

8. The emergency lighting system according to claim 7, characterized in that: The second alarm is a light emitting diode.

9. The emergency lighting system according to claim 7, characterized in that: The emergency lighting system further includes an operational amplifier U1D, wherein the non-inverting input terminal of the operational amplifier U1D is connected to the output terminal of the oscillation circuit, and the inverting input terminal of the operational amplifier U1D is connected to the output terminal, so as to ensure that the input signal is consistent with the output signal.

10. The emergency lighting system according to claim 1, characterized in that: The voltage stabilizing circuit is a three-terminal integrated voltage stabilizing circuit 7824, whose input and output terminals are grounded via capacitors respectively.

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